GB2143901A

GB2143901A - Internal combustion engine and frame assembly

Info

Publication number: GB2143901A
Application number: GB08418412A
Authority: GB
Inventors: Reinhard Konneker
Original assignee: Dr Ing HCF Porsche AG
Current assignee: Dr Ing HCF Porsche AG
Priority date: 1983-07-21
Filing date: 1984-07-19
Publication date: 1985-02-20
Also published as: IT8421914A1; DE3326321A1; IT8421914A0; JPS6036760A; FR2549533A1; FR2549533B1; IT1176397B; DE3326321C2; US4550698A; GB8418412D0; GB2143901B

Description

1

SPECIFICATION

Internal combustion engine and frame assembly The invention relates to an internal combus tion engine and frame assembly, more parti cularly although not exclusively a motorcycle underframe, comprising a cylinder head and a crankcase housing, the internal combustion engine being secured to the frame by holding members cooperating with the cylinder head and the crankcase housing.

In a known internal combustion engine (German Auslegeschrift Published Specifica- 80 tion] 1 064 832) of the type described above the holding member of the cylinder head comprises a lug directed laterally away there from. This design has the disadvantage that this arrangement does not introduce the stresses which arise in the cylinder head and the crankcase housing in an optimum manner, but rather these stresses cause moments which can lead to breakage of the lug. In addition, there are no reinforcing arrange ments provided on the crankcase housing, and so the assembly, comprising the internal combustion engine and the underframe, has not sufficient rigidity.

The object of the invention is therefore to provide arrangements on the cylinder head and on the crankshaft housing of an internal combustion engine such that in the first place the stresses which occur and which are intro- duced by way of the holding members may be absorbed properly and without distortion from the assembly which is formed by the underframe and the internal combustion engine.

The present invention consits in an internal combustion engine and frame assembly cornprising a cylinder head and a crankcase housing, the internal combustion engine being secured to the frame by holding members cooperating with the cylinder head and the crankcase housing, wherein the cylinder head holding member is disposed in a median plane of the cylinder and is joined to a support core provided inside the cylinder head and which extends as an attachment tie into the crankcase housing, and the support core and the attachment tie being connected to one another by threaded fastening members.

The main advantages attained by the inven- tion are that the arrangement of the holding member and the design of the support core in the cylinder head and of the attachment tie on the crankcase housing and also their connection by means of the fastening members pro- perly introduce into the internal combustion engine the forces which occur. In this way and in conjunction with the crankcase housing which preferably comprises a lower hollow part and an upper hollow part, both reinforced by walls, it is additionally made possible for GB 2 143 901 A 1 the internal combustion engine to form a rigid unit together with the frame. Sleeve-like castiron sections for bores receiving the fastening members may be easily integrated into the cylinder head and on account of their reduced height, which also affects the length and weight of the fastening members, also contribute to the optimization of the internal combustion engine in terms of weight. The inter- nal combustion engine may comprise two Vshaped cylinders disposed longitudinally of the frame, both cylinder heads being provided with support cores and being secured to the frame by means of holding members, and so a particularly rigid support arrangement is formed by the frame and the internal combustion engine.

In the accompanying drawings:

Fig. 1 is a cross-section through an internal combustion engine and frame assembly ac- cording to the present invention; Fig. 2 is an outline elevation of another internal combustion engine and frame asseffibly according to the present invention, and 90 Fig. 3 is a section on an enlarged scale taken along the line 111-111 of Fig. 1. An internal combustion engine shown in Fig. 1 is secured to a motorcycle underframe 2, and together they both form a support unit.

The internal combustion engine 1 comprises a cylinder head 3 and a crankcase housing 4 with the cylinder head 3 and crankcase housing 4 joined along a plane A-A and are secured to the underframe 2 by means of holding members 5, 6 and 7.

The holding member 5 of the cylinder head 3 is disposed in a median plane B-B of the cylinder and is joined to a support core 8 (Fig. 8) provided inside the cylinder head 3. The support core 8 is a component part of the cylinder head 3 and is supported between the outer walls 9 and 10 of the cylinder head 3.

In one part 11 of the crankcase housing 4, into which the cylinder 12 also extends, the support core 8 is continued as an attachment tie 13. The support core 8 and attachment tie 13 and, respectively, the cylinder head 3 and the crankcase housing 4 are connected together by bolts 14, 15. For this purpose the support core 8 has bores 16 and 17 and the attachment tie has threaded bores 18 and 19 receiving the bolts 14, 15.

The bores 16 and 17 are provided in sleeve-like cast-iron sections 20 and 21 which are symmetrical to the median plane B-B of the cylinder, but extend only over a portion C of the total height of the cylinder head 3. In order to render the bolts 14 and 15 accessible, recesses 22 and 23 are provided locally in the support core 8.

The crankcase housing 4 is formed by an upper hollow part 24 which contains the cylinder 12 and a lower hollow part 25, which are joined in a horizontal plane D-D and connected together by bolts 26 and 27.

Aligned vertical walls 28 and 29 formed in the upper and lower housing parts 24 and 25, respectively, act as a reinforcement and also separate a crankshaft chamber 30 (B is the centre of the crankshaft) and a transmission chamber 31 The lower housing part 25 extends to a vertical fastening portion 32 of the underframe 2, where it is held in position by the holding members 6 and 7, which are preferably bolts, threaded into lugs 33 and 34.

The holding member 5 of the cylinder head 3 is likewise a bolt (Fig. 3). A connection member 35 is fixedly mounted on the cylinder head 3 by means of a bolt 36. Whether use is made of only one holding member 5 and one connection member 35 or a plurality thereof, for the purpose of holding the cylinder head 3, is largely determined by structural con- siderations, e.g. whether the engine is single cylinder or twin cylinder construction.

A twin-cylinder internal combustion engine 37 is shown in Fig. 2, which comprises cylinders 38 and 39 arranged in a V-forma- tion. The cylinders 38 and 39 are orientated in the longitudinal direction E-E of the motorcycle underframe 44. In this arrangement both cylinder heads 40 and 41 are secured at the same height to the motorcycle underframe 44 by means of holding members 42 and 43, and the cylinder heads 40 and 41 are provided with support cores which correspond to the support core 8 and the other features already described above. The crankcase hous- ing 45 is secured to the motorcycle underframe as described and shown in Fig. 1.

Claims

1. An internal combustion engine and 4() frame assembly comprising a cylinder head and a crankcase housing, the internal combustion engine being secured to the frame by holding members cooperating with the cylinder head and the crankcase housing, wherein the cylinder head holding member is disposed in a median plane of the cylinder and is joined to a support core provided inside the cylinder head and which extends as an attachment tie into the crankcase housing, and the support core and the attachment tie being connected to one another by threaded fastening members.

2. An internal combustion engine and frame assembly according to Claim 1, wherein the crankcase housing is formed by an upper hollow part containing at least one cylinder and a lower hollow part, which parts are joined together along a horizontal plane and are reinforced by internal walls in the crankcase housing.

3. An internal combustion engine and frame assembly according to Claim 2, wherein the walls of the crankcase housing parts are aligned and extend in a vertical plane to divide the crankcase housing into two cham- GB 2 143 901 A 2 bers.

4. An internal combustion engine and frame assembly according to Claim 2 or 3, wherein the crankcase holding members are provided at least on the lower part.

5. An internal combustion engine and frame assembly according to any of Claims 1 to 4, wherein the support core has bores for the threaded fastening members, said bores extending symmetrically to the median plane of the cylinder and provided in sleeve-like cast-iron sections.

6. An internal combustion engine and frame assembly according to Claim 5, wherein the cast-iron sections extend over only a part of the total height of the cylinder head.

7. An internal combustion engine and frame assembly according to any of claims 1 to 6, wherein a connection member is pro- vided between the support core and the cylinder head holding member.

8. An internal combustion engine and frame assembly according to Claim 7, wherein the connection member is secured to the cylinder head by means of bolts.

9. An internal combustion engine and frame assembly as claimed in any of the preceding claims, wherein the engine has two cylinders arranged in Vformation and orien- tated in the longitudinally of the frame, each cylinder head having a support core secured at approximately the same height to the frame by means of the holding members.

An internal combustion engine and frame assembly substantially as described with reference to, and as illustrated in, Figs. 1 and 3, or Fig. 2 of the accompanying drawings.

Printed in the United Kingdom for Her Majesty's Stationery Office, Dd 8818935, 1985, 4235Published at The Patent Office, 25 Southampton Buildings, London, WC2A lAY, from which copies may be obtained.